A liquid crystal display device includes a pixel electrode whose potential is controlled by a thin film transistor, a common electrode whose common potential is controlled by a common signal, and a liquid crystal layer to which an electric field generated between the pixel electrode and the common electrode is applied. In the liquid crystal display device, the potential of the pixel electrode is controlled to change the electric field to be applied to the liquid crystal layer. In this manner, transmittance/non-transmittance of light from a backlight unit through the liquid crystal layer is controlled to display an image on a display surface of the liquid crystal display device.
The screen size of the liquid crystal display device increases and the resolution becomes higher. Hence the common potential supplying performance is desired to be further increased, and a liquid crystal display device having a higher common potential supplying performance is desired.